For high K_0, the Bell model's <f> can be negative. Fix pysawsim.test.bell_rate.

diff --git a/pysawsim/test/bell_rate.py b/pysawsim/test/bell_rate.py
index b7eb3f63c32618644a963bd05713a1a9b0b61d18..83ca86d9a855f6405024ceafaa798fe95072f84d 100644 (file)
--- a/pysawsim/test/bell_rate.py
+++ b/pysawsim/test/bell_rate.py
@@ -146,7 +146,7 @@ def bell_rate(sawsim_runner, num_domains=1, unfolding_rate=1,
     w = 0.1 * rho # calculate bin width (in force)
     force_mean = alpha - gamma_e * rho
     theory = Histogram()
-    theory.bin_edges = arange(start=0, stop=3*force_mean, step=w)
+    theory.bin_edges = arange(start=0, stop=max(force_mean,0)+3*rho, step=w)
     theory.bin_centers = theory.bin_edges[:-1] + w/2
     theory.counts = w*num_domains*N*probability_distribution(
         theory.bin_centers, [alpha, rho])